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1.
在现代生物科学中,应用生物卵壳亚微结构的物种特异性进行分类研究已成为可行性现实。在海洋生物学研究中,曾发现海胆类未受精的卵壳层颗粒中即存在着眀显的物种特异性差别( L?nning,1967)。很多学者通过对鱼类卵细胞发生期间的亚微结构及卵壳形成的研究,证实在鱼类卵壳结构中亦存在特异性的种间差异,并认为这些差异与分类学、生物学及其区系分布有密切关系( Müller& Sterba,1963; Yamamoto,1963;G?tting,1966; Anderson,1967; Flügel,1967)。目前我国对鱼类卵壳( Egg chorin)结构的研究还鲜为人知,本文亦是首次通过对12种海洋经济鱼类受精卵的卵壳结构差别的探讨,为进行鱼类系统分类和系统发育研究提供科学依据。  相似文献   

2.
黄海区太平洋鲱鱼(Clupea pallasi)目前为黄海重要经济鱼类之一,但世代波动大影响产量。在研究发育与人工增殖的实验中,静水孵化率低,特别在静水发育中的胚胎,位于卵块中间或底层的卵,自尾芽期后即开始不同程度的发育缓慢或停止发育。只有卵块边缘的卵或孤立的卵,才易发育与孵化。其发育程度  相似文献   

3.
采用鳗弧菌灭活疫苗对大菱鲆(Scophthalmus maximus)雌性亲鱼免疫方法, 进行了母源免疫对子代抗体水平、变化规律的影响及卵子中抗体蛋白空间分布特征的研究。结果表明, 免疫亲鱼产出的卵子中IgM抗体水平显著高于对照组。胚胎发育过程中, 抗体水平整体呈下降趋势, 且48h前下降迅速, 免疫组抗体水平显著高于对照组(P<0.05); 48h以后, 免疫组和对照组间无显著差异。卵子中抗体蛋白免疫组化定位结果表明, 未受精卵中IgM抗体集中分布在卵膜内侧边缘, 卵黄部分分布不明显。研究还发现, 卵巢液中抗体水平显著高于卵子匀浆液, 且免疫亲鱼组卵巢液中抗体水平显著高于对照组(P<0.05)。本实验验证了大菱鲆特异性抗体的母源传递性, 并揭示了在本免疫条件下的传递时效, 为进一步开展通过母源免疫对育苗早期疾病防控途径的探索奠定了基础。  相似文献   

4.
轮虫休眠卵研究进展   总被引:4,自引:0,他引:4  
综述了近年来国内外对轮虫休眠卵的研竞概况。重点介绍了轮虫休眠卵的形态、影响轮虫休眠卵形成的因素、轮虫休眠卵的萌发形式及影响其萌发的因素、自然水体中轮虫休眠卵的研究概况。  相似文献   

5.
石斑鱼鱼虱病的研究 Ⅴ.盐度对南海鱼虱存活的影响   总被引:1,自引:0,他引:1  
记述了盐度对南海鱼虱CaligusnanhaiensisWu&Pan不同发育期的影响。在盐度为10以上时,南海鱼虱的幼虫和成虫对盐度的变化有较大的忍耐性,盐度在10—40之间对幼虫和成虫存活没有明显的影响,24h的实验表明,存活率均为100%。然而,虫卵对盐度的变化较为敏感,虫卵孵化的最适盐度范围为20—35,超出此范围虫卵孵化受到影响。当盐度为10时,虽然孵化率可达100%,但孵出的幼虫活动能力差,多数附着于卵囊上而不能正常活动,不久即死亡。盐度为40时,卵子几乎不能孵化。在淡水中,虫卵、幼虫和成虫均不能正常生存。  相似文献   

6.
Egg identification in plankton samples is usually needed for purposes of stock assessment. Until recently, only morphological characters were used for identifying the eggs of different fish species. Late developmental stages are easily distinguishable due to pigmentation as well as egg and oil globule size range. However, for early stages, these characteristics are difficult to be discriminated and may overlap with other species. European horse mackerel species (Trachurus trachurus, T. mediterraneus, T. picturatus) overlap significantly in their spawning areas in some European waters. Because of the fact that their eggs are morphologically similar, genetic methodologies are needed to identify eggs and larvae to species correctly. In the present study, formalin‐ and ethanol‐preserved eggs were tested to estimate the efficacy of genetic methodologies for species identification of eggs when different preservatives are used. A 370‐bp fragment of cytochrome b was successfully amplified followed by restriction fragment analysis with two restriction enzymes aiming to identify the eggs to species. Horse mackerel egg identification was accomplished with the maximum success in ethanol‐preserved eggs. However, it seems that various preservatives had different effects on the DNA quality of eggs as genetic identification was less successful in formalin‐preserved eggs. Preserving in ethanol a part of the eggs obtained in plankton surveys is suggested for purposes of accurate genetic identification, even if their morphological features are distorted in time.  相似文献   

7.
东方扁虾卵巢和滤泡结构的研究   总被引:6,自引:0,他引:6  
卵巢包括4种形态的组分:(1)卵巢壁,(2)生殖上皮,(3)卵母细胞(早期卵巢还包括卵原细胞)一滤泡细胞层,(4)卵巢壁内突.卵巢壁及壁内突均含有血管、血窦、肌细胞等成分,卵巢壁内突延伸至每个滤泡的外层基膜处.滤泡由内至外由卵母细胞、卵周隙、滤泡细胞及基膜等4部分组成.卵母细胞膜表面向卵周隙内伸出许多微绒毛,并具有许多微吞饮凹.随着滤泡的发育,卵周隙内含物电子密度越来越大,成熟滤泡的卵周隙内含物演变为卵壳.卵壳由两部分构成:外层较薄,而内层较厚且含电子致密的颗粒物质.滤泡细胞一般为单层,具较强的合成活性,其合成产物系卵周隙内含物的一部分.东方扁虾卵巢和滤泡的结构特征表明外源性(卵母细胞外及卵巢外)的卵黄合成在卵黄发生上起重要的作用.  相似文献   

8.
汞等六种重金属对鱼卵孵化和仔鱼成活的影响   总被引:4,自引:0,他引:4  
为了解重金属对海洋鱼卵的孵化和仔鱼成活的毒性规律,对防止污染和保护水产资源提供科学依据,我们进行了六种重金属(Hg~( ),Cu~( ),Cd~( ),Zn~( ),Pb~( )和Cr~( ))对海洋鱼卵的孵化和仔鱼成活的毒性研究。 胶州湾是多种经济鱼类产卵和发育的场所,5月中旬—6月中旬,水温在15—17℃时是适宜的产卵季节,拖网常见的鱼卵约  相似文献   

9.
胶州湾内纺锤水蚤休眠卵的研究   总被引:5,自引:0,他引:5  
描述了胶州湾内双刺纺锤水蚤(Acrlia bifilasa)和太平洋纺锤水蚤(A.pacifica)卵的形态,揭示了底泥中休眠卵数量季节变动与种群数量变动的关系,并探讨了温度、盐度、泥覆盖等环境因子对休眠卵孵化率的影响。  相似文献   

10.
为深入了解卤虫卵生物学测定值与其品系间的相关性,选择青海尕海、新疆阿其克库勒湖、山西解池、山东埕口盐场、西藏 ( 具体地点不详 )、新疆鲸鱼湖以及西藏拉果错湖共 7 个品系的卤虫卵,进行了干卵、水合卵、脱壳卵卵径及卵亚壳层厚度的测定.统计结果显示卵径及卵的颜色与海拔高度密切相关,高海拔地区卤虫卵径大、颜色深;卤虫卵径的大小与其成体的生殖方式似乎无直接关联;以卤虫卵亚壳层厚度及卤虫卵径为依据的 Q-聚类结果一致,其中西藏、新疆鲸鱼湖、新疆阿其克库勒湖、以及西藏拉果错湖卤虫卵为一组,山西解池、山东埕口盐场、及青海尕海卤虫卵为一组.卤虫卵亚壳层厚度及卤虫卵径与卤虫品系之间均存在相关性.  相似文献   

11.
尝试了多种方法分离中国明对虾(Fenneropenaeus chinensis)囊胚细胞和原肠胚细胞并进行了细胞培养.结果表明,解剖法适用于囊胚细胞,自行设计的压片法适用于原肠胚细胞.在培养起始阶段,通过降低血清浓度和缩小培养体系可使中国明对虾囊胚细胞和原肠胚细胞迅速贴壁并铺展,囊胚细胞铺展后有明显的生长晕,中后期原肠胚细胞较易达到半汇聚状态.值得注意的是,中国明对虾囊胚细胞在不同培养液中培养可发生形态上的分化.本实验方法有望用于对虾细胞分化机理和对虾细胞建系的研究.  相似文献   

12.
Pelagic eggs of marine fish were collected weekly from shelf waters at Park Rynie on the KwaZulu-Natal south coast from 1987 to 2007 to investigate seasonal and annual patterns in the abundance of sardine Sardinops sagax eggs. After a sudden appearance in June each year, sardine eggs were found persistently throughout the winter–spring period before disappearing in early summer. From changes in the cross-shelf distribution of eggs, it is inferred that sardine shoals are close inshore in June, as they arrive in KwaZulu-Natal waters from the south, then the shoals disperse offshore and thereafter return inshore before their return migration southward in early summer. The period 2001–2007 yielded significantly fewer eggs than the previous 14 years of the study.  相似文献   

13.
褶臂尾轮虫(Brachionus plicatilis O.F. Müller,以下简称Bp)和圆形臂尾轮虫(B.rotundiformis Tschugunoff,简称Br)(Segers,1995)是轮虫门(Rotifera)单卵巢纲(Monogononta)的两个海水种或半咸水种,过去曾分别被认为是褶皱臂尾轮虫的L型和S型品系,现统称为褶皱臂尾轮虫复合种(B.plicatilis complex)(Yufera,2001)。由于该种分布广,在世界范围内被广泛用作多种海水鱼的种苗培育的重要开口饵料,因而成为单卵巢纲中最具经济意义和极受各国研究者关注的种类。作为单卵巢纲轮虫的共同特征Bp和Br轮虫进行无性生殖(或孤雌生殖)兼有性生殖,两种生殖世代交替发生而完成其生活周期,休眠卵即是有性生殖的最终产物——卵膜加厚的受精卵(King et al,1977a,b;Snell,1987).在实际生产中,休眠卵是轮虫储存、运输和孵化应用的最理想形式;而在生物学意义上,它不仅是轮虫用以抵抗或度过不良环境期,并向新的生存空间散布或拓展的特殊生活阶段,而且可通过一定时间的休眠和一定条件下的孵化,决定着下一生活周期的起始,从而控制着轮虫生活周期的节奏。尤其是休眠卵经孵化而启动新一轮无性生殖世代,一方面承传和实现了前一世代的遗传特性和基因重组结果,另一方面也为轮虫的生殖表现和遗传特性得以在新环境下产生新的适应性变化提供了条件。鉴于上述重要的实际和理论意义,多年来对休眠卵的休眠与孵化的研究深受各国学者的重视。Gilbert(1974)、 Pourriot等(1983)已就国际上的有关研究进行了详细综述,最近席贻龙等(1999)结合国内的有关报道对该领域的进展亦作了进一步概括。这些论述均泛指单卵巢纲诸多种类的休眠与孵化问题,且多数结果来自淡水轮虫的研究。本文的讨论将主要针对海水或半咸水的褶皱臂尾轮虫复合种,就有关调控或影响其休眠卵孵化的各种内、外因子及其作用机理的研究概况作一综述。  相似文献   

14.
从山东的盐场和新疆的盐湖采集了卤虫卵,进行了干燥、吸水和去壳的卵径、壳厚、无节幼体体长、染色体数目的生物学测定。按照文献[12]的分类,上述研究的卤虫,均属于第二类的孤雌生殖品系。盐湖的卤虫卵吸水和去壳后比盐场的卤虫卵大。而达板城东盐湖的无节幼体是最短的。各盐场的卤虫有2倍体、4倍体及5倍体,艾比湖的卤虫有2倍体和4倍体,达板城东盐湖只有4倍体。  相似文献   

15.
1994-1995年山东文登市高岛盐厂对虾育苗池和养虾池,随机和定点采集中国对虾的卵,无节幼体,蚤状幼体,糠虾幼体,仔虾及幼虾,成虾样品,利用透射电子显微镜对其进行病毒的检测。结果表明,卵细胞中含有大量的卵黄,没有明显的细胞分化,卵细胞质中有球形病毒感染;无节幼体的肝胰腺和上皮细胞的分化程度较低,有大量球形病毒分布;糠虾幼体已有明显的肝胰腺和上皮细胞的分化,肝胰腺上皮细胞的胞质中发现有球形病毒包涵  相似文献   

16.
1 Introduction M any estuarine and coastal copepods that havepreviously been classified as holoplankton m ightbestbe described as adultm eroplankton since they actuallyspend a portion oftheir life cycle in the seabed as rest-ing eggs [review ed by G rice and M arcus (1981) andM arcus (1996)]. R esting eggs can be extrem ely abun-dant (106 m ) in bays and estuaries especially w here -2w aterdepths are less than 20 m (M arcus,1989).Theyare likely to profoundly influence the dynam ics ofpel…  相似文献   

17.
Experiments were carried out on the toxicity of a fuel oil to developing embryos and juveniles of two marine amphipods. Parhyale hawaiensis eggs were able to develop from early germinal disc stage (early eggs) to juvenile form in concentrations of 10 (2 ppm) up to 40% (8 ppm) WSF, but deleterious effects were evident in hatching success of eggs and survival of juveniles at concentrations ≥ 10% WSF. The juveniles that hatched from those eggs in higher WSFs had greater mortality than the juveniles that hatched from the eggs exposed to lower WSFs. Survival of juveniles from late eggs (cephalic region differentiated) was also greater than those from early eggs. Amphithoe valida eggs were more sensitive to the WSF of fuel oil than the eggs of P. hawaiensis; < 10% of the test eggs hatched in the 4 ppm WSF compared with 66% of P. hawaiensis eggs at the same concentration. The toxicity of fuel oil to the two amphipod eggs is therefore dependent on the concentration and duration of exposure on the one hand, and on the developmental stages and probably the nature of the egg case on the other.  相似文献   

18.
Cape hake in Namibian waters are demersal and mesopelagic spawners, spawning peaking offshore between 100 and 400 m deep, depending on local environmental conditions. The cross-shelf circulation, low-oxygen layers and mesoscale gyres are three important environmental factors influencing hake spawning behaviour and subsequent transport of the spawning products. Normally, hake spawn offshore near the bottom at depths of 150–400 m. However, during one cruise, spawning was concentrated below several subsurface mesoscale gyres, resulting in reduced dispersion of the eggs and larvae. When the low-oxygen layer above the bottom is pronounced, hake spawning has been observed close to the top of the layer at oxygen concentrations as low as 0.2–0.3 m? ??1. The relatively small size of the eggs and their high specific gravity make them ascend quite slowly from the spawning depths, 10–40 m per day. Consequently, hake eggs spawned deeper than 200 m hatch before they reach the upper mixed layer. The newly hatched larvae are relatively undeveloped, without functional eyes or mouth, and display little swimming activity during their first hours, but laboratory observations have revealed subsequent periods of downward swimming activity. Based on current field observations, on buoyancy measurements of eggs and larvae and on observed larval behaviour, it is concluded that hake eggs and larvae are transported onshore by features of the upwelling subsurface circulation that compensate for offshore movement of surface water. This may be the basic mechanism concentrating early juvenile hake nearshore. Spawning activity near the low-oxygen layer might be a behavioural adaptation to minimize egg predation, because few other species are expected to survive such low concentrations of oxygen.  相似文献   

19.
超远缘鱼类—斑马鱼和泥鳅—受精卵的激光融合   总被引:2,自引:0,他引:2  
利用激光诱导方法对不同科鱼类,鲤科(Cyprinidae)的斑马鱼(Brachydanio Rerio)和鳅科(Cobitidae)的大鳞副泥鳅(Paramisgurnus dabryanus Sauvage)受精卵进行的融合实验结果表明:不同科间的鱼类受精卵可以融合并继续存活发育,有的可发育至初孵仔鱼。但是,其融合、发育表现出与亲缘关系较近的鱼卵的融合、发育有较大的差异。  相似文献   

20.
1Introduction Benthic -pelagic coupling refers to the two -way exchange or flux of matter between benthic andpelagic environments in aquatic systems. Most stud-ies have focused on the deposition of non-living or-ganic matter to the seabed, resuspension an…  相似文献   

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